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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | -1 |
| 3 | -1 |
| 4 | 0 |
| 5 | 0 |
| 6 | 1 |
| 7 | 0 |
| 8 | 0 |
| 9 | -1 |
| 10 | 1 |
| 11 | 0 |
| 12 | 1 |
| 13 | -1 |
| 14 | 1 |
| 15 | -1 |
| 16 | 1 |
| 17 | -2 |
| 18 | 2 |
| 19 | -2 |
| 20 | 2 |
| 21 | -2 |
| 22 | 3 |
| 23 | -4 |
| 24 | 3 |
| 25 | -4 |
| 26 | 5 |
| 27 | -5 |
| 28 | 6 |
| 29 | -6 |
| 30 | 7 |
| 31 | -8 |
| 32 | 9 |
| 33 | -9 |
| 34 | 11 |
| 35 | -12 |
| 36 | 13 |
| 37 | -16 |
| 38 | 15 |
| 39 | -17 |
| 40 | 20 |
| 41 | -22 |
| 42 | 23 |
| 43 | -26 |
| 44 | 29 |
| 45 | -30 |
| 46 | 35 |
| 47 | -38 |
| 48 | 40 |
| 49 | -45 |
| 50 | 50 |
| 51 | -52 |
| 52 | 58 |
| 53 | -65 |
| 54 | 69 |
| 55 | -75 |
| 56 | 82 |
| 57 | -89 |
| 58 | 96 |
| 59 | -107 |
| 60 | 114 |
| 61 | -123 |
| 62 | 135 |
| 63 | -145 |
| 64 | 158 |
| 65 | -170 |
| 66 | 185 |
| 67 | -200 |
| 68 | 216 |
| 69 | -232 |
| 70 | 251 |
[1,0,-1,-1,0,0,1,0,0,-1,1,0,1,-1,1,-1,1,-2,2,-2,2, -2,3,-4,3,-4,5,-5,6,-6,7,-8,9,-9,11,-12,13,-16,15, -17,20,-22,23,-26,29,-30,35,-38,40,-45,50,-52,58, -65,69,-75,82,-89,96,-107,114,-123,135,-145,158, -170,185,-200,216,-232,251] |